U-PB DETRITAL ZIRCON GEOCHRONOLOGY OF THE CAROLINA TERRANE IN CENTRAL SOUTH CAROLINA

The Carolina Terrane (CT) is considered to be an exotic island-arc system that accreted to Laurentia during the middle to late Paleozoic. In central South Carolina (SC), CT is the easternmost exposed crustal block in the southern Appalachian Orogen and is peri-Gondwanan in origin. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was used to determine ages for more than 849 detrital zircons found in the CT of central SC. These zircons were extracted from the low-grade metasedimentary rocks of the Emory, Richtex and Asbill Pond formations. U-Pb detrital zircon age distributions do not contain the characteristic 1.0-1.3 Ga peaks associated with the Grenville Orogeny, which is consistent with other better characterized parts of the Carolina Terrane and demonstrative of its exotic origin. Age distributions are dominated by ages that fall between ca. 530-650 Ma, suggestive of a similar provenance, and these ages are consistent with age distributions found within the Albemarle Group and Hyco Arc in North Carolina. However, two samples have distinct age populations at ca. 520 Ma, younger than observed in the northern extent of the Carolina Terrane. These results change minimum depositional age constraints for the CT of central SC, which must be at least 12 Ma younger than observed elsewhere in the Albemarle group.